Railcar coupler locks typically have three positions: locked, unlocked and lock set. The lock set position allows couplers to be released when the railcars are pulled apart. Coupler assemblies sometimes do not operate properly in lock set, with the knuckle of the coupler jammed against the lock, preventing proper knuckle rotation. In some cases, knuckle and lock interference occurs in lock set. This requires the user to lift and hold the uncoupling lever in its most raised position to facilitate uncoupling, rather than lifting the handle to position the lock into lockset and remaining in that position so the operator can let go of the uncoupling lever. Holding the uncoupling lever in the raised position to ensure the coupler is unlocked while cars are being coupled or uncoupled can be a safety concern and is not recommended. When addressing lock set jamming concerns between the knuckle and lock, the traditional focus to resolve the problem was on the lock and its interface with the thrower.
The options can be limiting if the focus is just on the components in previous patents, such as U.S. Pat. Nos. 2,350,470; 2,709,007; 3,850,312; 4,084,705 and 4,363,414, all of which are herein incorporated by reference in their entirety. The options are also limiting when the focus is only on the mating parts of the system.
Other disadvantages may have also included the inability to completely measure (scan) to a very accurate level (+/−0.001″) all the surfaces of each component (either theoretically or from actual production parts), to create a very accurate CAD model (+/−0.001″) of each part, and then create a working CAD assembly of the system. Furthermore, the designer may not have the ability to use that model to investigate the issues, and to model and then simulate the proposed design changes to optimize the model. In the past, it is surmised that the companies with the design engineering capabilities were either not interested in, unable to undertake the time, devote the engineering resources, and/or spend the money necessary to investigate the concerns to the detail necessary to identify the concern, and then design a fix to these concerns. Modern day computer software and hardware are now available (at an attainable cost) and provide the tools necessary so that those that are experts in the field can use these tools to address these issues that were here-to-for left unaddressed.
There is a need to improve knuckle rotation to eliminate jamming while in lock set without delineating significantly from the accepted coupler assembly.